Method of packaging articles



Nov. 14, 1961 M. E. WALLIS 3,008,834.

METHOD OF PACKAGING ARTICLES Filed June 10, 1957 3 Sheets-Sheet 1 INVENTOR: a MARVIN E. WALLIS Nov. 14, 1961 M. E. WALLIS 3,008,834

METHOD OF PACKAGING ARTICLES Filed June 10, 1957 3 Sheets-Sheet 2 FIG.4 5

FIG. 5

INVENTOR:

MARVIN E. WALLIS Nov. 14, 1961 M. E. WALLIS METHOD OF PACKAGING ARTICLES 3 Sheets-Sheet 5 Filed June 10, 1957 INVENTOR. BYMARVIN E. WALLIS United States Patent "ice 3, 34v METHOD OF PACKAGING ARTICLES E; Wallis, 5811 S. Grant St, Hinsdale, Ill. Filed June 10, 1957, Ser. No. 664,529 SCIaims. (Cl. 99*166) This invention relates to the packaging art, and although concerned primarily with the packaging of comestibles, such as frozen or chilled meat products and the like, also contemplates packaging or formation of a protective and/or decorative coating onor around articles and objects other than comestibles, regardless of their shape or nature.

Heretofore, various methods and apparatus have been devised for applying. a protective coating to comestibles such as cheese, meat cuts and the like to aid in the preservation thereof, as well as so-called table-ready meats which have been previously smoked or cooked. Among the types of coatings commonly employed for this purpose are gelatin, caul fat, wax basecoatings of varying compositions and. the like, all of which are designed to form. an integral. covering for the articles undergoing treatment. Various methods have been devised for the application of such coatings: and among these are dipping, spraying, drenching, enrobing and impact application of the coating material to the surface I of the articles undergoing treatment, a wide variety of apparatus being employed to accomplish these methods of application'.'

The various methods which have been devised forthe application of such coatings to the surface of such comestibles" have not, in practice, proven satisfactory, particularly from a packaging standpoint Where it is desired that the finished packaged product shall have an attractive appearance. One outstanding difficulty that has been encountered, particularly in connection with dipping processes, resides in the inability to apply a coating which will firmly adhere to the exposed surfaces of the product at all points and portions thereof' The presence of small pockets or crevices, occasioned by irregularities in the contour of the surfaces frequently lead to air bubble holes in the coating. 7 Additionally, as a result of the temperature differential between the relatively hot liquid coating material and the relatively cool surface of the product, any vapor pressure which developed within the confines of the coating would forcethe coating away from the surface of the product and leave a space between the coating and prod- Where the coating is of an infiexible' or brittle nature, splitting or other forms of rupture of the coating was likely to occur at such separated regions. A separatedor ruptured coatingof this nature is not only unsightly in appearance, but it is also undesirable from the standpoint of handling and consequent contamina: tion of any exposed surfaces of the product resulting therefrom. Additionally, due to the large body of heated liquid within which the product was immersed, surface heating of the meat resulted in consequent deterioration. In general, the principal requisite of acoating of the type under discussion is that it shall cling or adhere closely to the surface of the product and it has been found that methods of application of a coating which involve dipping operations do not satisfy this requirement.

Where -so-calledenrobing operations are performed to effect a coating on the surface of meats and other comcstibles, the appearance of the finished package must be sacrificed. As a matter of fact, enrobing operations wherein a curtain of the coating material is caused to descend upon the article and to flow over the top and around the sides thereof, are not suitable for packaging operations and are employed mainly for coating the cores the application to the comestibles.

3,008,834 Patented Nov.- 14,1961- of confection bars with an outer covering of an edible confection, as, for example, chocolate, in the manufacture' of candy bars. Where enrobing operations are employed for food preservation or packaging purposes, the relative thickness of the coating applied and the irregularity obtained in the thickness thereofmakes it extremely ditficult to'att'ain a transparent coating giving good visibilityof the product, while at the same time the volume of coating material applied to any given article subjects the same to the limitations which have been described above in connection with dipping processes, namely, surface heating of. the product and the presence of. air bubble holes. Additionally, the cost of such coatings will be excessive due to the quantity of coating material consumed.

Spraying operations, utilizing spray heads or atomizin'g nozzles for the application of the coating to comestibles also are possessed of numerous limitations, principal among which is the difliculty of applying viscous coatings evenly and without the use of solvents. Frequently, when spraying is resorted to, the initial spray particles applied to any given article,v particularly where chilled or frozen productslare concerned, have a tendency to solidify upon contact with-the surface of the article and thus create a;dus t-; onthe-surface and; subsequently applied particles arrivingat the surface of the article do not have suflicient heat; content to againmelt the previously deposited particles so that a coating is applied which, in the last analysis, is of a crumbly and uneven nature and is, therefore, liable, to rupture. Additional-1y, due to the irregular contour Y of. many types of such frozen comestibles, the application of a spray to the moving articles by one or more fixedly positioned spray nozzles will result inthe creation of relatively thick coating applications wherea given surface is normal to the spray nozzle and a relatively. thin coating application where a given surface is inclined relative to the spray nozzle. Finally, a built-up coating of the type applied; by spray deposition; on the surface of the article will be uneven due to the lack of any means for constantly adjusting the direction of spray to the uneven contourfof the article so that small pocketsand other voids will be overfilled with the coating material, thusresulting in dense and sparse coating regions which present anunsightly and tensile strength, the ability to harden rapidly, ease of stripping from the coated product, and durability over a given period of time. However, the use of such coatings for packaging: purposes has not been widespread inas m uch as no suitable means has been found for making Dipping, enrobing, spraying and other known methods of coating have not proven feasible due to the thickness of the resultant coating, its high cost and the high temperatures involved.

The present invention is designed to overcome the above noted limitations that are. attendant upon the use of conventional dipping, enrobing, spraying, drenching and other methods and apparat'us for coating articles and, toward this end, it contemplates the provision of a novel method whereby the articles undergoing packaging or coating are caused to intercept one or' more flowing" sheet-like films issuing; from one or more film headscapabl'e of producing such films and whereby, in passing through such film or films, the surface of the articles become coated by a ski-called laying down process wherein the films are progressively applied to'the surface in a uniform manner with uniform thickness throughout the entire surface area undergoing coating. According to the present process, the article is passed successively through a series of such flowing films and the various films are so directed inwardly of the path of movement of the article at various angles relative thereto that portions of the films will be applied to the exposed topand side surfaces of the article coextensively. The viscosity of the various flowing liquid films, the pressure main tained at the film heads which produce the flowing films, and the rate of travel of the article along its path of movement and into intersecting relation with the successive films, are carefully controlled according to, the present invention so that theintercepted portions of the films will be applied to the various surfaces without substantially diminishing the thickness of the flowing film and without allowing the same to accumulate or pile up on the surface of the article, and, furthermore, temperature conditions in the vicinity of the various film applying stations are carefully maintained so that complete hardening of a previously applied film will not take place until after the next succeeding film has been applied to the surface of the article for sealing juncture with the previously deposited film. In this manner, a sealed package coating will be applied to the article which will completely envelop the surfaces to which it is applied and which is of uniform thickness throughout.

' The provision of a method of the character briefly outlined above being among the principal objects of the invention, it is another object to provide'a novel method of applying a coating to the surface of articles wherein the films'are applied to the surfaces of the article by a low impact process wherein each surface undergoing coating has applied thereto dual coating films with the second coating being applied over the first coating prior to complete hardening of the former coating so that the two coatings will blend uniformly into a single homogeneous covering under the influence of thermal conditions maintained in the vicinity of the applied coating.

A still further object of the invention is to provide such a method whereby the individual films aredirected against the surfaces of the article at respective angles whereby the exposed side surfaces of any irregularities such as protrusions, crevices; cracks, pockets and the like '-will be completely coated with a film of uniform thickness and wherein the film will follow the natural contour of the surface to which it is applied without appreciable change in thickness at any region therealongl In this manner, a protective coating which is of uniform appearance is assured and which is devoid of unduly transparent or opaque regions.

Yet another object of the invention is to provide such a method wherein the relatively low temperature maintained by the product undergoing coating is conducive toward rapid hardening of the liquid film after application to the surface of the product so that despite the fact that the ambient temperature in the vicinity of the product is higher than the melting point of the applied coating, the packaged product will emerge from the process ready for instant handling thereof.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel product and method by which it is made substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of theclaims.

The accompanying drawings illustrate one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and inwhich:

FIG. 1 is a fragmentary perspective view, somewhat schematic in its representation, illustrating one form of apparatus by means of which the packaing method of the present invention may be carried out;

FIG. 2 is an enlarged sectional view taken substantially along the vertical plane indicated by the line 2--2 of FIG. 1;

FIG. 3 is a fragmentary perspective view of a vertically adjustable bottom coating thickness control mechanism employed in connection with the present invention;

FIG. 4 is an enlarged sectional view taken substantially along the vertical plane indicated by the line 44 of FIG. 1;

FIG. 5 is a sectional view taken substantially along the line 55 of FIG. 4;

FIG. 6 is an enlarged sectional view taken substantially along the vertical plane indicated by the line 6-6 of FIG. 1;

FIG. 7 is a schematic view of the apparatus illustrating principally the hydraulicsystem associated therewith;

FIG. 8 is an enlarged fragmentary detail perspective view of a portion of the apparatus illustrating the manner in which certain of the film-forming nozzles associated with the same may be adjusted;

FIG. 9 is an enlarged detail fragmentary perspective view of a portion of the structure shown in FIG. 8;

FIG. 10 is an enlarged detail fragmentary perspective view of another portion of the structure showninPIG.

8; and

FIG. 11' is a perspective view of'one of the filmproducing nozzles or film heads employed in connection with the present invention.

Referring now to the drawings in detail and in particular to FIGS. 1 and 2, which illustrate generally one form of apparatus for carrying out the .method'of this invention, the comestibles or other articles A, to be packaged are carried upon a moving endless conveyor band 10,

' associated with a conveyor assembly 1 1. The forward end of the conveyor band passes over an idler roller or drum 12 and the rear end thereof passes over a driving roller or drum 14. The rollers 12 and 14 are suitably mounted on shafts 16 and 18, respectively, which shafts are adapted to be rotatably journalled in the framework of the machine.

The complete machine framework is not disclosed in the schematic illustration of the invention and only portions thereof appear at selected locations in the various views of the drawings, the reference numeral 20 being applied. in each instance to the illustrated portion of the framework. The shaft 18 constitutes the driving shaft for the conveyor assembly 11 and it is adapted to be driven by a belt and pulley arrangement 22 from an electric motor 24 suitably carried on the machine framework.

The endless conveyor band '10 has an upper straightaway portion 26 and a lower return portion 28. ,In its medial region the straightaway portion 26 isin-terrupted by a dip, so to speak, as at 30 (see particularly FIG. .2) and this downwardly displaced portion 30 partially encloses -a bottom coating device designated in its entirety by the numeral 3-2. The interruption thus provided in the medial region of the straightaway portion 26 divides the same into a forward section 26a and a rear section 26b, the former being in register at its extreme forward end with a feed table 33, and the latter being in register at its rearmost end with the straighta-way portion 34 of an endless belt 36 associated with a discharge conveyor assembly 38, only a portion of which has been shown in FIG; 1. The forward end of the endless belt 36 passes over a roller or drum 40 suitably journalled in the machine framework. The conveyor band .10 is preferably formed of stainless steel wire mesh material and its direction of movement is illustrated by the arrows in FIG. 1, as is also the direction of movement of the endless conveyor belt 36.

The conveyor assembly 11 is enclosed within a generally rectangular casing or cabinet, the outlines Of WhiQh are shown in dotted lines at 42. The details of the easing 42 form no part of the present invention and it will be understood that the same will, of course, be provided with suitable entrance and exit openings in the front and rear walls thereof for introduction of the articles A undergoing packaging to the'forward end of the conveyor 11 and for transfer of the packaged articles from the rear end' of the conveyor 11 to the discharge conveyor 38, the latter conveyor being disposed exteriorly of the casing 42.

The casing 42 may be formed of stainless sheet steel and the top and side walls thereof may be provided with one or more cover plates and access openings at appropriate regions therein. The casing 42 serves the multiple purpose of shielding the internal operative packaging mechanism, including the conveyor assembly 11 and the articles undergoing packaging. thereon from contamination and from the effects of ambient conditions of temperature and humidity, of retaining the heat generated within the casing 42 for film conditioning purposes, and of serving .as a splash guard for preventing egress of the filth forming liquid from the immediate. vicinity of the apparatus, either during operation of the apparatuslor during adjustment. of they various film-producing nozzles or film heads. V

The articles A which, forillustrative purposes, maybe in the form of stacks of sliced luncheon meat with the individual slices thereof being generally of rectangular configuration so that the finished package will be of rectilinear design, are fed to the conveyor and are adapted to progress along the straightaway portion 26 of the con veyor band 10 from a point of entrance into the casing 42 to a point of discharge where the completely packaged articles pass over a bottom film thickness control mechanism 43 which has been illustrated in detail in FIG. 3, and are transferred to the discharge-conveyor 38.

In passing along the straightaway portion 26 of the conveyor '10, the various articles A encounter a plurality of flowing liquid films orfilm-like sheets, six such films being illustrated herein and being designated at f1, f2, f3, f4, f and f6, respectively. These films issue from a series of six nozzlesor film heads 44, 46, 48, 50, 52v and 54, respectively, with the film heads being arranged along the straightaway portion 26 of the conveyor in longitudinally spaced relationship sequentially in the. order named. The various film heads may be substantially identical in construction, although the specific design of the same may, if desired, be varied so as to producevfilms having diiferent characteristics. One of the nozzles, namely the nozzle 44, has been shown in detail in FIG. 11 and the character and function thereof -willbe described subsequently. While six such nozzles and the films issuing therefrom have been illustrated herein by way of example, it will be understood that a greater or lesser number of such film heads may be employed'if desired to accommodate various types of package coatings-on the articles, as well asto accommodate differently shaped articles. Ordinarily, however, it will be found that for articles of apolygonal nature with either planar or curved sides, the use of six such film heads properly arranged along the conveyor straightaway portion 26, will suffice to apply a dual thickness package coating to the exposed sides and tops of the articles in a manner that will be made clear presently.

The composition of the liquid films issuing from the various film heads may vary widely but, in general, a compounded liquid wax having; a-medium or high viscosity and having a melting point in the neighborhood of 150 F, will be found suitable for application to comestibles; particularly edible meats which are processed at low temperatures, i.e., frozen meats and the like. Numerous compositions have been found suitable as a packaging: coating: for such comestibles and it will be understood that the particular composition selected will 6 vary according to the article to which it is to be applied, and also according to the quality and physical character'- istics of the-package coating desired. H

Certain liquid materials when applied to the article'sA and hardened thereon Will be almost completely transparent while other films will present a package coating which is translucent or opaque. The liquid materials employed for the films may also vary as to color and various shades of films are contemplated by. the use of suitable coloring additives. In addition to wax base films, various plastic materials such as polyethylene and the like have been found suitable for use in connection with the packaging of comestibles.

One specific material capable of use in connection with the present invention as a film material and consequently as a hardened package coating for comestibles of the type under consideration is a microcrystalline wax derived from a paraflin base crude oil. As a wax coating this material has extremely high tensile strength and a low coefficient of expansion. Another specific material which has been found suitable as a film material according to the present process of packaging comestibles such as frozen or chilled meats and the like consists of acetylated monoglycerides and ethyl cellulose, combined in a manner which will produce a high viscosity film which, when hardened as a coating for. the articles, also has high tensile strength and a low coefficient of expansion, asw'ell as a relatively'low melting point.

No claim is made herein to any novelty associated with the particular material used for the fluid films' f1, f2, f3, or to the specific coating produced thereby whenthese films have become hardened on the articles'A' since variousother materials are available foruse and still other materials may be developed by experimentation which.

will subsequently be found suitable. It is deemed sulficient for purposes of description herein to st'atethat the particular liquid material employed must possess a relatively high viscosity at the low temperatures involved while the material is in film form so that it will have sufficient tenacity to hold together as a solid unbroken sheet over an area at least as large as the surface or surfaces of the article to which it is to be applied, and it must also have high tensile strength when hardened on the surface of the article to avoid rupture under normal conditions of handling of the packaged product.

Additionally, the film, in its hardened. state as a coating material must be non-toxic, odorless, tasteless, have a low'coefiicient of expansion upon hardening so as to avoid the production of folds or Wrinkles in. the coating, be chemically inert'with respect'to the substance to which it is applied, and be'impervious to moisture and exhibit no osmotic tendencies. Finally, the hardened coating must possess suflicient tensile strength that it may readily be stripped from the comcstible to render the latter accessible for use. Irrespective, however, of the particular composition employed for the various films" f1, f2, f3, etc., the essential featuresof the invention are at all timespreserved'.

Still referringto FIG. 1, the various film heads 44,- 46, 48, 50, 52' and 54 are disposed in the vicinity of the straightaway portion 26 of the conveyor 11 in positions where they will direct their streams of liquid inwardly toward the path of travel of the articles A at dilferent angles and in different directions, generally horizontally against the sides of the articles passing along the conveyor and generally vertically downwardly against the tops of the articles; Collectively, the six nozzles or fihn heads are adapted to apply a uniform continuous imperforate coating to the four sides and top of each article passing through the casing or cabinet 42 on the conveyor 11 by a two-stage coating process, while the bottom coating mechanism 32 is adapted'to apply a uniform homogeneous imperforat'e coating to the bottom of the article, this latter coating automatically becomingsealed to the side coatings so that the four side coatings, the top coating and the bottom coating constitutes a sealed enclosure or envelope for the article, the six sides thereof having intimate coextensive contact with the side faces of the article.

As will become apparent presently when the nature of the invention is better understood, the coating or covering which is thus applied to the article on all sides or surfaces thereof is of a unique character in that it is of uniform thickness throughout, regardless of the contour of the surfaces of the article. The coating or covering is thus to be distinguished from the type of coating which is ordinarily applied to articles by so-called enrobing machines wherein a sheet or ribbon of the coating material is directed or spread on the articles or cores and allowed to settle around the four sides thereof, thus filling all voids completely.

The various nozzles or film heads associated with the conveyor 11 are maintained supplied with the film-forming material or coating substance through a system of piping from a reservoir which may be in the form of a collector sump maintained at the bottom of the casing or cabinet 42 and into which the liquid material issuing from the film heads may flow by gravity for continuous recirculation through the system. The specific arrangement of the piping will vary for difierent installations but for exemplarypurposesa system suitable for the present illustrated installation has been schematically shown in FIG. 7 wherein a manifold pipe 60 is op eratively connected through a series of six branch pipes 62 to the various film heads, and through. additional branch pipes 64 and 65 leading to the opposite ends of the bottom coating apparatus 32. The molten liquid coating material iswithdrawn from the sump 66 through a conduit 68 leading to the intake side 69 of a pump 70, driven by motor 70', and the discharge side 71 of the pump 70 is connected through a conduit 72 to the manifold pipe 60. Replacement liquid may be supplied to the system by introduction thereof into the casing or cabinet 42 where it will find its way by gravity to the sump 66.

The film-forming material is maintained slightly above its melting temperature at a point where the desired flow characteristics are exhibited, by suitable electrical heating apparatus. Additionally, in order to maintain the interior of the cabinet 42 at a constant even temperature and to provide a blanket of warm air over the inlet and outlet ends of the cabinet, a series of infra-red lamps 73 are provided. These lamps give uniform heating throughout the cabinet 42, and also afford visibility of the mechanism contained within the cabinet and facilitate inspection of the film characteristics which may obtain at any of the various film heads at any given in stant. The heat generated by the heating instrumentalities 73 is to a large extent retained within the cabinet 42 and is uniformly distributed throughout the interior thereof where it serves'to maintain the various moving parts at the proper working temperature so that the wax, plastic or other film-forming material will not harden thereon.

Still referring to FIG. 1, and in addition to FIGS. 4, Sand 6, the film heads 44 and 46 are associated with the conveyor straightaway portion 26a and are disposed in longitudinally spaced relation along one edge of the conveyor band in or near the horizontal plane of the straightaway portion and are arranged to direct their respective liquid films f1 and f2 in a generally horizontal direction inwardly of the conveyor structure and across the upper face of the moving band 10. -As shown in FIGS. 1 and 4, the film f1 emerges or issues from the film head 44 and fans out, so to speak, in the form of a relatively thin generally planar liquid sheet or film. The effective angle of direction of the film head 44 is such that the upper edge of the film follows a generally parabolic path of motion similar to the trajectory of a projectile projected into. space at the same angle. An approximation of the cross sectional area of the film is shown in FIG/5 and it will be noted that along the upper edge of the film there is a thickened portion 72 which is occasioned by a phenomenon which is termed herein as a rope effect inasmuch as it gives a visual simulation of a rope along the upper edge of the film This so-called rope gives substance to the film and creates a body of the flowing liquid material from which liquid particles flow across the film structure. The film also exhibits a rope effect as at 74 along its lower edge. The pressure of liquid issuing from the nozzle or head 44 is suficiently great as to carry the unbroken film completely across the width of the conveyor band 10 or, at least -a suificient distance removed from the head that when the film is intercepted by the oncoming article A undergoing coating, the side or sides of the article opposing or facing the head will interrupt the film and establish a cut-off point 76 (FIG. 4) while the portion 78 of the film not intercepted by the article will be carried completely over the top of the article so as to clear the same and allow the liquid film to be discharged downwardly within the cabinet or casing 42 in the general direction indicated by the arrows. The film f1 will maintain its unbroken continuity as it arches over the top of the moving article A and it will break as indicated at 80 at some region beyond the article into streams or droplets for subsequent collection in the sump 66.

As will become clear presently during the description of the mechanism shown in FIGS. 8, 9 and 10, means are provided for adjusting the angularity of the various film heads 44, 46, 48, etc., as well as for adjusting the lateral positions of these film heads relative to the axis of the conveyor 11, i.e., their distance from the said axis, such adjustments being provided to accommodate different installations, as well as to accommodate the shape characteristics of difierent articles undergoing packaging. In connection with the rectilinear articles A selected for illustrative purposes herein, the first nozzle or film head 44 in the series of film heads is arranged at the side of the conveyor band 10 so that the vertical plane of the film fl is inclined forwardly at an angle of from approximately 30 to approximately 45 with respect to the transverse direction of the conveyor as clearly shown in FIG. 1. Hence, when the moving article A intercepts the film, a portion of the film will be applied progressively to the vertical side of the article which directly opposes orfaces the film head 44 and, thereafter, as the article progresses along the axis of the conveyor, a portion of the film will be progressively applied to the trailing vertical side of the article.

For convenience of description, the four vertical sides of the article -A have been designated a, b, c, and d, respectively, while the top and bottom faces of the article are designated at e and 7, respectively. The side a is the leading side of the article. The side 0 is the trailing side. The sides b and d are the right hand and left hand sides of the article asviewed in FIG. 1. Due to the forward inclination of the plane of the film f1 as previously described, it will be seen that as the article progresses through the vertical plane of the film, a portion of the film will be applied to the sides d and c progressively in the order named.

In connection with the application of the film f1 to the sides d and c of the articles A as just described, the pressure maintained at the film head 44, the viscosity of the liquid film, and the speed of travel of the article A along the axis of the conveyor are so related to one another that the film will be applied to the surfaces of the article uniformly. In general, the linear speed of movement of the flowing film f1 and the linear speed of movement of the article A will be so correlated that the portion of the film intercepted by the article will be uniformly placed upon the sides of the article without appreciable film flow on the surface of the article after the film has contacted the sides thereof. Where the article is allowed to exceed-a certain predetermined rate of motion, there is danger of interrupting the continuity of the film as it is deposited on the surface of the article. Where the article does not proceed along the conveyor at a sufficient rate of motion, the film will build up on the surface o'ftheanticle and fiow downwardly on'the surface in the manner encountered during conventional enrobing operations. By properly adjusting the various factors men'- tioned above, both film interruption and film flow or bunching of portions of the film on the surfaces of the article will be avoided and a uniform film coating which accurately follows the contour of the surface of the article will be attained. It should be-noted at this time that since the temperature of the film is maintained slightly above the melting point of the film substance, and since the articles are maintained at temperatures considerably below such meltin'gpoint, especially in the case of frozen meat products, the applied relatively thin film coating will" harden shortly after application to the surfaces of the article. The temperature maintained Within the cabinet 42 and other temperature factors, conditions of film viscosity, speed of film projection and other physical phenomena are carefully controlled so that complete hardening of the applied coating issuing from the film head-44 will not take place before subsequently applied overlapping or joining films are applied'to the article by the other film heads so that a uniform and substantially homogeneous package coating will ultimately be applied to the articles A. i

It will be observed by an inspection of FIG. 4' that during passage of an article A through the film 1, free flowof the liquid film in the lower regions thereof is interrupted by the left hand edge of the rectilinear article, while no obstruction is presented to such free flow of the film in the upper regions thereof. Since the direction: of the film head 44' is such thatthe film possesses both vertical upward andtransverse components of motion relative to the conveyor, the upper portion of the film will arch in parabolic fashion and pass completely across the article and span the conveyor band 10 with a sharp cut-off taking place at'76 as previously described and with the projected film portion 78 clearing theupper face of the article and leaving this'face completely devoid of F any "film deposition;

Referring again to FIG. 1, the article A which has emerged from the film f1. with a film coating on the sides d. and -'e thereof will subsequently encounter the film f2. The film head 46 which supplies the film f2 is sopositiorred that the film has both an upward vertical com ponent of motion and a transverse component of motion whilethe plane of the film is inclined rearwardly'at an angle-to the path of travel of the articles A. Due to such inclination of the film' 2 it' will be seen that as the article progresses through the vertical plane of the film, a por- 5 tion thereof will be progressively applied sequentially to the side a and to the previously deposited film on the side din theord'er'named. While-a certain amount of solidification of the previously deposited film on the erally downwardly onto the top surface of the article and at a slight forward inclination relative-to a vertical transverseplane. The film f3 is generally fan-shaped as clearl'y shown in FIG. 6 with thickened rope eifects being present as shown at 84- along the upper marginal edges of the film. Otherwise, the cross sectional characteristics of the film are similar to that which has been illustratedin FIG. 5 in connection with the film f1. The lower portion of the film f3 is somewhat wider than the maximum transverse width of the article A and, since thefilm f3 and article A are substantially centered on the conveyor band, the forward edge of the article will initially penetrate the film and establish two cut-oif points 8 2 and 8-3 where the film f3 is intercepted by the longitudinal upper side edges of the article A. As the article progresses through the plane of the flowing film, a coating will be progressively applied tothe top surface e of the article while the uninterrupted portions 86 and 88 of the film will clear the sides d and b with these portions breaking at 90 and 92 in the vicinity of the plane of the upper straightaway portion 26a of the conveyor.

From the film f3; the article A emerges with the four faces thereof; namely thefaces a, c, d and e at least partially coated 'coextensively and proceeds along the conveyor path to the bottom coating mechanism 32 by means of which a coating of the materialis applied to the-underneath face in a manner that will be described subsequently. The partly coated article A is transferred from the straightaway portion 26a to the straightaway portion 26b asit traverses the bottom coating mechanism 3'2-and thereafter it encounters the film f4.

The nozzle 50 which produces the film f4 is positioned centrally above the straightaway portion 26a of the conveyor band 10 and is arranged to direct its continuous film of coating material generally downwardly onto the previously deposited film on the surface b of the article A at a slight rearward inclination relative to the vertical sided may take place during passage of the article from the film1f 1 to the film f2, due to=eontact of the film with the relatively cold product comprising the article A; such preliminary hardening will not prevent the two coatings unitinglandforming a unitary homogeneous film mass which completely covers the side :1. The same phenomenon': of film cut-off and parabolic arching of the over the topof the articleA will obtain as-the article encounters the film fl" and passes therethrough and this "phenomenon need not be again described.

From the filnr f2; thearticle A, now fully coated on one side and with a partial completely coextensive coating on two other sides, will proceed along the conveyor H to the'fil'm f3 which issues from the" nozzle 482 This latter nozzle-is-positioned cent-rally over the straightaway portion 26a of the conveyor band 11) and is arranged to direct its: continuous liquid film of coating material gentransverse plane of the conveyor 11. The character and shape of the film f4 is substantially identical with the character'and shape of the film f3 and similar coating effects are obtained whereby the uninterrupted portion of the film clears the sides b and d of the article A as previously described in connection with the film f3.

The opposite inclinations ofthe two films f3 and f4'to insure complete coating of all sides of any pockets or shallow depressions which may be present in the upper face e of the article A, the film f3 accommodating the forwardly disposed walls of such depressions or pockets and the film f4 accommodating the rearwardly disposed walls of such depression due to the respective angles of impact of the films on the face e of the article. Upon emerging from the film M the article will be fully coated on the: upper surface with a homogeneous film of the material of the desired thickness, with other full coatings existing on the sides d and bottom face j. Partial coatings will exist as previously described on the sides a and c. 1

The film f5; which is the next film encountered by the partly coated article- A, is similar to the previously described filmsf1 and f2 but it issues from the nozzle 52 at the right hand side of the conveyor band 10 as seen in FIG; 1. The nozzle 52' imparts to the film f5 components of both upward vertical and transverse motion with the vertical plane of the film being-inclined forwardly relative to theipath of travel of the articles along theconveyor 11 so that as the film is intercepted by the partially coated article A, a coating will be applied to full or partial coatings coextensively covering the six sides thereof and with only the sides aand b remaining partially coated. The film f6, when encountered by the article A, supplies the final coating to the sides a and b by depositing the interrupted portion of the flowing film progressively onto these two sides in the order named with cut-01f and arching effects being present as previously described in connection with the films f1, f2 and f5. The fully coated article A then emerges from the film f6 and is caused to move across the bottom film thickness control mechanism 43 and be deposited on the conveyor belt 36 from whence it may be conducted to a point of discharge.

Referring noW to the details of the bottom coating mechanism 32 which is best illustrated in FIGS. 1 and 2, it will be seen that, this mechanism is interposed between the two conveyor band sections 26a and 26b at the region 33 where the conveyor band 10 makes a dip as previously described. The dip 30 is produced by an elongated generally semi-cylindrical trough-like member 160 which may be formed of stainless sheet steel and which has its open side presented upwardly. The member 100 extends across the conveyor with its ends suitably anchored in the machine framework and thus located a slight distance below the level of the straightaway portion 26 of the conveyor band 10. Also extending across the conveyor with their ends anchored in the machine framework are a pair of spaced parallel fixed bars 102 and 104, respectively. These bars are positioned substantially in the plane of the straightaway portion 26 and the conveyor band 10 passes forwardly over the rearmost bar 104 and then extends downwardly around the curved underneath side of the member 100 and proceeds upwardly where it passes over the fixed bar 102. From the above description, it will be seen that any given point on the moving conveyor band 10 will pass from the straightaway portion 26a over the bar 104 downwardly and upwardly around the member 100 and over the bar 102 and proceed along the straightaway portion 26b.

The bottom coating mechanism 32 is disposed Within the hollow of the trough-like member 100 and it includes an elongated rectilinear box-like casing 106 which may be formed of stainless steel sheet material having an imperforate bottom wall 108, upwardly and inwardly inclined front and rear walls 110 and 112, respectively, and a perforate top wall 114 provided with a plurality of small holes or openings 116. The holes 116 are preferably arranged in three parallel rows although it will be understood, of course, that any desired arrangement of the holes may be resorted to, providing these spaced holes are well distributed throughout the area of the rectangular top wall 114. The casing 106 is prm vided with side walls 115 and 117, respectively, each of which is formed with an opening 118 therethrough in communication with the manifold pipe 60 through the previously mentioned branch pipes 64 and 65.

The level of the top wall 114 is maintained slightly below the level of the straightaway portion of the. conveyor to afford a slight clearance for passage of the bottomwall f of the various articles A over the bottom coating mechanism 32 as the same are transferred from the conveyor straightaway portion 26a to the straightaway portion 26b. Liquid coating material introduced into the casing 106 under prmsure will substantially fill the same and be forced outwardly through the various holes 116 as shown in FIG. 2 to provide a series of closely spaced jets, streams, or the like which are directed upwardly toward the bottom surface of the article passing thereover. These various jets serve to apply a coating to the bottom surface of the article, and, in a sense, it may be said that the bottom coating arrangement thus serves to float the articles across the gap between the 1W0 straightaway portions 26a and 26b of the conveyor.

The bottom thickness control mechanism 43 which is best illustrated, in FIGS. 1 and 3, is in the form of a shallow, vertically adjustable U-shaped brackethaving a base 122 and upstanding side flanges 124. Each side flange 124 has welded or otherwise secured thereto a lug 126 which threadedly receives therethrough an elevating screw 128 each screw being rotatably journalled as at 130 in a portion of the machine framework 20. The lower end of the elevating screws 128 carry bevel gears 132 which mesh with similar bevel gears 4134 provided on a transverse shaft 136 suitably journalled in the machine framework 20. The upper end of one of the elevating screws 128 is adapted to receive thereon a crank arm 138 by means of which the screw may be turned in either direction to initiate raising and lowering movements of the bracket 120.

The bracket 120 constitutes a carriage for a plurality of horizontally disposed parallel idler rollers 140, the opposite ends of which are rotatably journalled as at 142 in the side flanges 124 of the carriage bracket 120. The elevation of the carriage bracket 120 is normally maintained at a point at which the rollers are normally slightly below the plane of the upper surfaceof the straightaway portion 26 of the conveyor. The carriage bracket 120 is adapted to be adjusted up and down so that the rollers may be caused to engage the coating which has been applied to the underneath surface of the articles A as the articles pass from thestraightaway. portion 26b of the conveyor band 10 to the conveyor belt 36 of the conveyor 38. The rollers 140 make actual contact with the underneath surface of the film and thus smooth out any irregularities that may occur on the surface of the film as well as to remove any solid particles which may adhere to the coating. By vertically adjusting the height of the carriage bracket 120, the thickness of the bottom film may be controlled.

FIGS. 8, 9 and 10, illustrate one form of mechanism whereby the angularity of the various film heads 44, 46, 48, etc. may be adjusted within very fine limits to raise or lower the respective films produced thereby, and whereby the various film heads on opposite sides of the conveyor structure may be bodily shifted in unison inwardly or outwardly toward and away from the path of travel of articles on the conveyor band to accommodate articles of different widths. It will be understood, of course, that the means illustrated herein to effect these adjustments are purely exemplary and that other means for adjusting the positions of the nozzles may be employed if desired. While in the schematic illustration of FIG. 7 a single manifold pipe 60 supplies all of the film heads, the arrangement of FIG. 8 involves the use of plural manifolds and I152, one for each set of film heads on opposite sides of the conveyor structure. Depending branch pipes 154 and i156 lead from the manifold pipe '150 to the film heads 44 and 46, respectively. Similarly branch pipes 158 and 160 extend from the manifold pipe 152 to the film head 52 and 54. The various branch pipes 154, 156, 158 and 160 are supported in individual supporting blocks 162 and these blocks on one side of the conveyor are carried on a rock shaft 164 and those on the other side of the conveyor are similarly carried on a rock shaft 166. The two rock shafts 164 and 166 are each mounted for limited rocking movement in a pair of depending end flanges 168 provided on a supporting plate 170. The two supporting plates 17 0 are mounted for sliding movement toward and away from each other on a pair of guide rods 172 fixedly mounted on the machine framework 20. Each supporting plate 170 also has a pair of depending side flanges 174 through which the guide rods 172 extend so that the supporting plates 170 may be slid in either direction transversely of the conveyor assembly. Means operable under the control of a single crank arm, as will be described subsequently, are provided for selectively and regulably causing the two supporting plates 170 to be thus moved toward and away from each other transversely of the conveyor.

-By turning the rock shafts 164 and 166 about their axes in a manner to be described, the filn'i heads- 44, 46, 52. and 54 may be swung in arcs to raise or lower the sheets or films issuing therefrom, and by rotating the film heads about their respective branch pipes 154, 156, 158 and. 160, the angle atwhich the sheets or films cross the: conveyor maybe varied. Thus, by combinations of the various adjustments of which the filmheads are capable',.the same may be connectively and individually adjustedrthrough a wide range of positions.

In: order to effect movement of the two supporting plates 170 toward and away from each other, each plate has mounted thereon a pair of spaced angle brackets 180 and1'82, respectively. The brackets 180 are adjustably carried on their respective supporting plates 170 for limited transverse adjustment and are capable of being clamped in any desired position of adjustment by clamping bolts 183. Extending through the two angle brackets 1 80- transversely of the conveyor assembly is an adjustment screw 1 84-, the screw being threadedly received in the two brackets by means of threads of opposite pitch. Similarly, an adjusting screw 186- having threads of opposite pitch is threadedly received in the two angle brackets 182. V

The two adjusting screws 184 and 186 are constrained to rotate in unison but in opposite directions by means ofa pair of intermeshing gears 188 and 190 carried on the adjusting screws 184 and 186, respectively. The gear 188 is fixedly secured to the adjusting screw 184 while the gear 190 is slidably keyed to the screw 186 as. at 192 so that this latter gear may be moved into and out of mesh with the gear 188 as desired. One. end of the ad'- justing screw 186 is squared as at 194 for torque transmit-ting engagement in the socket portion 196 (FIG. of a suitable operating handle or crank 198 by means of which the adjusting screw 186, as well as the adjusting screw'184 when the latter is operatively geared thereto, may be turned in opposite directions.

From the above description, it will beseen'that when the two gears. 188 and 190 are in mesh as shown in. FIG. 8 and the adjusting screw 186 is turned in one direction or the other, the supporting plates 170 will be constrained to-move toward or away from each other as the case may be, thus carrying with them the manifold connections which they support thereby increasing or decreasing the distance between the depending branch pipes on opposite sides of the conveyor structure and varying the distance of the filmheads from the center line of. the straightway portion of the conveyor. 7 Each bracket 182 is formed with a slot- 200 therein into which slot' there extends the distal end of a pin 202 carriedon' an arm- 204 fixedly secured to one of the rock shafts 164 or 166 and thus it will be seen that when the gear 190 is moved along. the adjusting screw 186 so that it. is out of register with the gear 188 as shownin FIG. 10' and the. clamping bolts 183 are loosened so that the bracekts are freev to move independently of. the support: ing. plates 170 on. which they are mounted, turningzmovement of the adjusting screw 184 inone direction or. the other will cause the brackets 180 to be moved toward or away from each other, as the case may be, while the sup porting plates 170 remain. stationary. Such movement of the brackets 180 will be: translated through the pins 202 to the arms 204,. thus. rocking; the tworock shafts 1.64 and 1-66'inopposite directions and causing the pairs of branch pipes 154, 156- and 158, 160 to be swung towardv and away from each other, thus varyingv the distance-between the opposed sets. of film heads. as well as altering their angulan'ty to a slight degree.

3 Although. the specific construction of they film heads used; to produce the films employed hereirr and. designated 351-, f2, f3, et'c.,.they all may be like the: film head 44' specifically illustratedin FIGURE. 11. The film headthere shown: is in the formof, a unitary casting. preferably formed of brass. It has agenerally cylindrical configurationand is formedat oneend with a threaded nipple 250 by means of which it may be threadedly received in the lower end of the branch pipe 154 with which it is associated. Immediately forwardly of the nipple 250, the casting is formed with a polygonal section 251, for reception of a wrench whereby the angularity of the film head as a whole may be adjusted about its axis.

The forward end of the casting is reduced as at 252 and a recess 254 formed in one side thereof provides a proximate wall 256, atrough-like bottom 258 and a distal wall 260; A central bore 261 extends longitudinally inwardly from the threaded end of the film head and communicafes with the recess 254: through a discharge orifice 262 which intersects the recess 254 adjacent the trough-like bottom 258and in opposition-to the distal wall 260. The distal surface 260 broadly comprises the liquid deflecting and film-controlling surface. This surface is more or less sharplycurved adjacent to its base and it flattens out in the regionsremote from the trough-like portion 258 into" a planar surface which may be disposed at an angle of approximately to the longitudinal axis of the film head casting.

Liquid issuing from the discharge orifice 262 is directed' against the surface 260 near the base thereof in a concentrated central region. The impact of the stream of liquid issuing from the orifice 262 against the surface 260 causes the same to fan out, so to speak, and follow the contour of the surface 260, constantly changing its direction of travel until such time as it is thrown or forced radially outwardly from the edge regions of the surface 260, at which time a sheet of the liquid having diverging sides with rope-like edges as shown at 72 and 7'4 in FIGS;

'4'and 5. is produced. It will be understood that the specific shape of the deflecting surface may be varied to produce moving films which vary widely in film form or shape, film thickness, film density and the like. Additionally, the angle which the planar portion of the surface 260 assumes relative to the longitudinal axis of the film head casting may be varied from a relatively small angle to an angle which is even in excess of 90 so that the direction of flow of the film will be reentrant with respect to the flow of liquid issuing from the orifice 262; Inv general, it may be stated that the higher the viscosity of the liquid employed, the more severe will be the angle throughwhich the: liquid is deflected in passing from the orifice 262 into the body of the film.

To recapitulate, the streams of coating material discharged from the nozzles of the socalled film heads, are in the form of thin, unbroken flat streams or flowing sheets: of liquid faning out from their respective nozzles andextending across the path of the advancing articles to be coated. Where each film or sheet crosses the path of the advancing articles it is large enough to have the articles pass therethrough between its divergent edges and still. leave undisturbed an appreciable portion of the sheet a between the article and at leastoneedge thereof. Hence, the area of the portion of the sheet through which the articlespass islarger than the total projected area of the surfaces of the articles which oppose or face the sheet. or

film, either squarely or obliquely. The molecular content of the sheets or films moves generally horizontally inwardly of the path of the advancing articles, i.e. generally horizontally across said path, in the case of the sheets or films which coat the sides of the article, and generally downwardly onto the path in the case of the sheet or film which forms the top; of the package.

The sheets: or films which coat the sides of the articles are: disposed at oblique angles of between 30 and 45 tothe path of the articles, and the sheets or films which cover the top of the articles are slightly inclined. Thus, as the articles intercept the sheets or films, the intercepted portionsthereof are laid unbrokenly onto the intercepting surfaces of the articles.

As. will: be readily apparent, the temperature inside the casing 42' must be sufiiciently high to maintain the coat- 15 ing material in its liquid state. What this temperature should be depends upon the nature of the specific coating material. Where a microcrystalline wax is employed, this temperature should be in the neighborhood of 150 F. For other materials which possess a lower melting point, the temperature can be correspondingly less.

Whatever material is chosen for the coating, it should have a relatively low melting point, for instance 110 F. to 140 or 150 F., and it must be hard enough at room temperatures to permit normal handling. Also, it should have a coefiicient of viscosity of at least 25 to 5000 centipoises when in its liquid film state. Best results are obtained when the viscosity is quite high, for then there is less likelihood that the sheet or film will break or vary substantially in thickness as it lays itself onto the surfaces of the article, which squarely or obliquely oppose the molecular flow of the film as the article intercepts it. t

The selection of a suitable coating material and of the temperature needed to maintain it in a liquid state, as well as the pressure required to form it and maintain it in a flowing sheet or film will present no difficulty to those skilled in the art. *By the same token, no difliculty will be experienced in coordinating the rate of flow of the liquid forming the sheet with the rate of advance of the articles. Obviously, if the articles advance too fast the film laid thereon may be too thin or even broken, and if the advance of the articles is too slow, the coating ma terial will tend to pile up on the intercepting surfaces thereof. The ideal condition is one in which the intercepted portion of the film is deflected out of the plane of the sheet and laid unbrokenly, and without change in thickness, onto the opposing surfaces of the article, where it immediately begins to congeal.

Having thus described the invention what I claim as new and desire to secure by Letters Patent is:

1. The method of packaging a comestible article by the application thereto of a surface coating of a highly viscous liquid which hardens at room temperatures, said method comprising continuously advancing the article in a horizontal path through a coating zone, discharging the highly viscous liquid at a temperature above the melting point thereof to the atmosphere in said zone in the form of a pair of generally oppositely directed non-intersecting continuous thin unbroken planar films, with said films disposed edgewise substantially perpendicularly to said path and extending from the bottom of the path to a height at least as great as the height of the article and with the molecular content of said films moving generally horizontally inwardly of said horizontal path from opposite sides thereof whereby the article is caused to pass through said films and interrupt the inward molecular flow thereof and receive on all surfaces thereof which oppose the direction of molecular flow of one of said films an unbroken coating of the material, and receive on all surfaces thereof which oppose the direction of molecular flow of the other fi'hn an unbroken coating of the material, whereby all lateral surfaces, at least, of the article will become coated with the liquid material. 2. The method of claim 1, wherein the planar films are so directed that the planes thereof extend obliquely and at opposite angles to the path of movement of the article.

3. The method of claim 2, wherein the angles at which the planar films cross the path of movement of the article lies between 30 and 45 4. The method of packaging an article in a hermetically sealed sheath and simultaneously forming the sheath of a material which is a highly viscous liquid at temperatures above a predetermined minimum and which rapidly congeals and sets at temperatures below sai drninimum, which method is characterized by the steps of: maintain ing a supply of the sheath-forming material in its liquid highly viscous state; forcibly discharging a stream of liquid sheath-forming material from said supply thereof into a packaging zone and simultaneously shaping said stream into a thin unbroken planar sheet of liquid having edges which diverge from its point of discharge, and

which sheet is of a size large enough to have the article being packaged pass therethrough between its diverging edges and still leave undisturbed an appreciable portion of the sheet between the article and at least one of said edges; effecting relative bodily motion between the sheet and the article along a path which intersects the plane of the sheet and brings the article through a portion of the sheet which has an edge to edge dimension greater than-the corresponding dimension of the article so that those surface portions of the article which oppose the flow of the liquid forming the sheet intercept said flow; and so coordinating the rate of flow of the liquid forming the sheet with the rate of relative bodily motion between the sheet and the article that the intercepted portion of the flowing liquid is deflected out of the plane of the sheet and laid unbrokenly onto said surface portions of the article where it immediately begins to .congeal, while the nonintercepted portion of the flowing liquid continues in an unbroken sheet beyond the far reaches of the article.

S. The method of claim 4 characterized further by repeating the defined contact between the article and the sheet, with diiferent surface portions of the article opposing the flow of the liquid forming the sheet, as often as needed to form a complete sheath about the article.

6. The method of covering a preselected area of the surface of an article with a protective film of material which is a highly viscous liquid at temperatures above a predetermined minimum, and which rapidly congeals and sets at temperatures below said minimum, characterized by the steps of: advancing the article along a defined path through a film applying zone; maintaining a supply of the film forming material in its liquid highly viscous state; forcibly discharging a plurality of non-intersecting streams of liquid film forming material from said supply thereof into said film applying zone and simultaneously shaping said streams into non-intersecting thin unbroken planar sheets, each of which has divergent edges, with the planes of the sheets generally crosswise of and intersected by the path of travel of the article; and so aiming the streams which form the sheets that flowing material from a first sheet is intercepted by only certain surface portions of said preselected area and is thereby deflected out of the plane'of said first sheet and progressively laid in the form of an unbroken film onto said certain surface portions to cover the same as the article passes through the fihn applying zone, while other adjoining surface portions of said preselected area are sheltered from the material flowing in said first sheet and intercept and deflect flowing material from a second sheet to be similarly covered thereby as material from said second sheet is laid unbrokenly and progressively on said other adjoining surface portions.

7. The method of packaging a comestible article which comprises: continuously advancing the article in a straight horizontal path through a heated coating zone; discharging a highly viscous liquid which is capable of hardening at room temperature, from a point at one side of sa d path into said zone in the form of a first continuous thin unbroken substantially vertical planar sheet having edges which diverge from said point, the lower edge of which is substantially horizontal and substantially no higher than the level of the bottom of said path and the top edge of which arches upwardly over the path to a height at least as great as the height of the article, with the molecular content of the sheet flowing generally horizont-ally inwardly from the point of origin of the sheet so that as the article moves through said first sheet all surfaces of the article which oppose the direction of molecular flow of the sheet deflect said flow and have he tl ifl cttid portion of the sheet laid thereon; discharging more of the highly viscous liquid from a point at the other side of the path, into said zone in the form of a second sheet which is similar in all respects to said first sheet so that the surfaces of the article at the other side thereof are covered as the article moves through the second sheet; and discharging more of; the highly viscous liquid from a point above the pathof the article, into said Zone and in the form of a third continuous thin unbroken planar sheet having edges which diverge from its point of origimthe width of which sheet in said path of the article is at leastas wide as the article and the molecular content of which moves generally vertically downwardly toward said path, whereby the article moving along said path is caused to move through said third sheet and to interrupt the downward molecular flow thereof, and receive on all upwardly facing surfaces of the article an unbroken coating of said material.

8. The method of claim 7 further, characterized by discharging more of the highly viscous liquid into said zone in the form of a plurality of upwardly directed 18 streams emanating from a point below said path with the molecular content of said streams moving generally vertically upwardly toward said path, whereby the article upon traversing said upwardly moving streams receives on all downwardly facing surf-aces thereof an unbroken coating of the viscous liquid.

References Cited in the file of this patent UNITED STATESPATENTS 1,556,472 Bailey Oct. 6, 1925 1,761,132 Lauhoif June 3, 1930 2,014,646 Christian et al. Sept. 17, 1935 2,119,910 [Ferry June 7, 1938 2,352,611 Bowers July 4, 1944 2,659,338 Harrison Nov. 17, 1953 2,708,635 Draper May 17, 1955 2,723,645 Garapolo Nov. 15, 1955 2,799,242 Cain July 16, 1957 

1. THE METHOD OF PACKAGING A COMESTIBLE ARTICLE BY THE APPLICATION THERETO OF A SURFACE COATING OF A HIGHLY VISCOUS LIQUID WHICH HARDENS AT ROOM TEMPERATURES, SAID METHOD COMPRISING CONTINUOUSLY ADVANCING THE ARTICLE IN A HORIZONTAL PATH THROUGH A COATING ZONE, DISCHARGING THE HIGHLY VISCOUS LIQUID AT A TEMPERATURE ABOVE THE MELTING POINT THEREOF TO THE ATMOSPHERE IN SAD ZONE IN THE FORM OF A PAIR OF GENERALLY OPPOSITELY DIRECTED NON-INTERSECTING CONTINUOUS THIN UNBROKEN PLANAR FILMS, WITH SAID FILMS DISPOSED EDGEWISE SUBSTANTIALLY PERPENDICULARLY TO SAID PATH AND EXTENDING FROM THE BOTTOM OF THE PATH TO A HEIGHT AT LEAST AS GREAT AS THE HEIGHT OF THE ARTICLE AND WITH THE MOLECULAR CONTENT OF SAID FILMS MOVING GENERALLY HORIZONTALLY INWARDLY OF SAID HORIZONTAL PATH FROM OPPOSITE SIDES THEREOF WHEREBY THE ARTICLE IS CAUSED TO PASS THROUGH SAID FILMS AND INTERRUPT THE INWARD MOLECULAR FLOW THEREOF AND RECEIVE ON ALL SURFACES THEREOF WHICH OPPOSE THE DIRECTION OF MOLECULAR FLOW OF ONE OF SAID FILMS AN UNBROKEN COATING OF THE MATERIAL, AND RECEIVE ON ALL SURFACES THEREOF WHICH OPPOSE THE DIRECTION OF MOLECULAR FLOW OF THE OTHER FILM AN UNBROKEN COATING OF MATERIAL, WHREBY ALL LATRAL SURFACES, AT LEAST, OF THE ARTICLE WILL BECOME COATED WITH THE LIQUID MATERIAL. 